Description: (Applicant's Description) The Microarray Core provides a centralized resource for services, materials and equipment required for performing large-scale gene expression studies utilizing cDNA and oligonucleotide-based microarrays. Microarray technology has developed at a rapid pace; however, the high cost burden of the instrumentation and biological resources makes the technology too expensive for most laboratories. Since microarray analysis is broadly applicable across all areas of research represented at the Cancer Center, the Microarray Core Facility is a logical mechanism to provide access to this powerful technology. By combining microarray resources into a shared facility, it is possible for all research programs within the Center to conduct gene expression profiling studies. In addition to making microarray technology generally available, providing microarray services through a shared resource has additional benefits relating to applications development. From the total annual operating cost of $479,465, we are requesting $66,336 from the CCSG allocation, an amount that represents approximately 14 percent of the total operating budget. These funds will support a portion of Facility staff salaries and service contracts.